Not to be outdone in this literary war of words, Liu's commentary was followed by another from Japan's ambassador to the United Kingdom, Keiichi Hayashi:

"There are two paths open to China. One is to seek dialogue, and abide by the rule of law. The other is to play the role of Voldemort in the region by letting loose the evil of an arms race and escalation of tensions," he wrote in the same paper.

The riposte prompted Chinese state media to warn "a war of public opinion between China and Japan is now in full swing."

"There are no flying cannonballs in the battlefield of public opinion, but it still requires the unity of the entire Chinese society to fight this war," The Global Times, a tabloid owned by the Chinese Communist Party mouthpiece The People's Daily, said on its website on Tuesday.

However, Internet users in both countries seemed amused rather than alarmed by the latest and surreal twist in the long-running diplomatic tit-for-tat.

"I think China and Japan are more like two kids who have not grown up," posted @Xiaowei Huang on China's popular Twitter-like platform Weibo.

"The method is refreshing and the cultural reference down to earth," said another Weibo user with the handle @luotiehang.

In Japan, Twitter user @emtyusuke welcomed the debate: "It is good to use wit and rhetoric to appeal each other's claim, without being overly emotional."

Abe's visit to the Yasukuni Shrine exacerbated tensions at a time when relations between Japan and China have been strained over the sovereignty of a set of islands in the East China Sea known as the Diaoyu islands in China and the Senkakus in Japan.

Asia's disputed islands

At first sight it looks like a scene from a post-apocalyptic movie. Journalist Tomas Etzler travels to one of the most remote locations in the South China Sea -- the front line of a dispute between the Philippines and China.